The present invention relates to electric sockets and more particularly to a truck electrical socket having enhanced connection capacity.
Heavy duty trucks are composed of a tractor and one or more trailers coupled in series to the rear portion of the tractor. The trailers are equipped with various electrical devices which are powered from the tractor. To establish an electrical connection between the tractor and the trailer, an electrical cable is connected between the back of the tractor and the front of the trailer. This connection is also made between trailers if the truck rig includes a plurality of trailers.
The electrical cable has six or seven (usually seven) conductors and suitable plugs at each end of the cable. The plugs are connectible to cooperating six or seven contact sockets mounted, respectively, in the rear wall of the tractor cab and the front end of the trailer. The basic geometries of those sockets and plugs are the subject of applicable SAE (Society of Automotive Engineers) standards, specifically SAE standard J560, a copy of which is present in the prosecution history (official record) of this patent. Standardizing the geometries of the sockets and plugs ensures that any trailer can be electrically connected to any tractor using any cable assembly. SAE standard J560 is incorporated hereinto by reference.
FIG. 1 shows a known socket assembly 10. The socket assembly 10 can be installed on the front of the trailer facing the back of the tractor or on the back of the tractor facing the front of the trailer. Socket assembly 10 includes a front face 12 which carries seven male pins in an array per SAE standard J560. One of the pins is a common terminal. The seven pins extend into the inside of the sleeve 18 and form the socket receptacle into which the end of the electrical cable connecting the tractor and the trailer is plugged. The socket receptacle is closeable by a spring loaded door 20.
The rear face 14 of the socket assembly 10 carries a service connection stud 22 for each non-common terminal disposed on the front face 12. Electrical conductors from the circuits of electrical and/or electronic equipment are connected to the service connection studs 22 of the socket assembly 10. Traditionally, loop lugs or spade lugs have been used to connect the electrical conductors to the service connection studs 22 of the socket assembly 10. This connection method has several disadvantages.
With increasingly complicated electrical systems, there is an increasing need for additional service connection points at a rear of a socket assembly 10. This is especially true for circuits designed with parallel legs that have a plurality of live ends that need to be installed on the same terminal. In the traditional socket assembly 10, this type of connection requires the loop lugs to be stacked on top of each other on a single service connection stud 22. This process is inefficient because the wires of the electrical conductors are stiff and hard to maneuver. There is also a limited space within which to fit all of the loop lugs. These restrictions make assembly difficult and time consuming.
Accordingly, it would be desirable to have an improved socket assembly with an enhanced capacity to accept electrical connectors.
It would be further desirable to create a connection system that is uncomplicated and efficient.
The present invention significantly enhances a socket""s capacity to accept electrical connectors, allowing up to a maximum of twenty-eight connectors in a presently preferred form of the invention. Additionally, the electrical connectors can be configured to simply plug into the electrical conductors, simplifying the connection process and minimizing the assembly time required to make the connection.
The present invention provides an electric socket assembly having a socket sleeve, an insert disc, a socket cap and a plurality of plug extenders. The insert disc carries a common pin and a plurality of non-common pins on its front face and service connection studs on its rear face. Each service connection stud is electrically connected to a respective pin. A socket cap having a plurality of pockets is positioned over the service connection studs such that each service connection stud extends through an opening in the respective pocket of the cap. A plug extender is positioned in each of the pockets of the cap such that the service connection stud extending through the opening in the pocket also extends through an opening in the plug extender. The plug extender includes additional service connection studs to enhance the connection capacity of the socket assembly. The plug extender is secured in the pocket using a fastener.
In another embodiment of the present invention, the invention is implemented in an electric socket assembly for truck tractors and trailers. The electric socket assembly includes a socket sleeve open at one end and having mounted therein a common connection pin and plural non-common connection pins. The connection pins and the sleeve at and adjacent its open end define a receptacle which is matable with a plug at an end of a tractor-trailer or trailer-trailer interconnection cable. The receptacle and the plug conform to a standard pertinent to electrical interconnections between truck tractors and trailers. The sleeve has features which adapt it for mounting directly in an opening into a truck tractor or trailer with its open end adjacent an outer surface of the tractor or trailer. In that context, the improvement is that in which at least some of the connection pins at ends thereof opposite from the sleeve open end have plural service connection terminals conductively connected to them.
In an alternative embodiment of the present invention, the socket assembly may include circuit breakers. Each circuit breaker has a fused terminal and a non-fused terminal. When circuit breakers are used, the non-fused terminal of each circuit breaker is electrically connected to a non-common pin. The fused terminal of the circuit breaker is extended through an opening in the socket cap and through an opening in the plug extender. The fused terminal becomes the service connection stud for connecting the electrical conductors from the circuits of electronic equipment.